Ever tried a magic square?
In a magic square, all the numbers across each row down each column and along each diagonal all add up to the same sum.
In this interactive game, the square is divided up into three rows and three columns, making nine boxes, each with a number in except for one. That final box is where you need to type the number that you think belongs there.
To work it out, add together the numbers in another line, then subtract the numbers in the line featuring the missing number.
Dealing with numbers with two decimal places and involving addition and subtraction, this is a challenge suitable for fifth and sixth graders.
Each time you complete a grid correctly, you can call up a new problem, so go and work your mathematical magic!